BASIC SCIENCE & PATHOLOGY

UNUSUAL SUBCHONDRAL LESIONS OF THE FEMORAL HEAD

Hee Joong Kim, Heung Sik Kang*, Young-Min Kim
Department of Orthopaedic Surgery and *Department of Diagnostic Radiology, Seoul National University College of Medicine, Seoul, Korea

We are reporting three cases of unusual subchondral lesions of the femoral head in two patients. A 24-year-old man presented with bilateral hip pain. Simple radiographs showed crescent sign with irregularity of the subchondral bone in the right femoral head and no abnormality in the left. On MRI, bone marrow edema pattern was observed in both femoral heads. Inside of the edema pattern, subchondral curvilinear band was identified. Both lesions disappeared spontaneously in the follow-up x-rays and MRIs.

A 52-year-old man with osteogenesis imperpecta was seen because of right hip pain. Simple radiographs demonstrated diffuse osteopenia in the right proximal femur. MRI showed diffuse bone marrow edema pattern in the right proximal femur. There was linear subchondral band in the superior aspect of the head. Drilling was done from the lateral cortex of the proximal femur to the subchondral lesion. Abnormal findings disappeared in the follow-up x-rays and MRIs.